Differential communication links, sometimes referred to as “high speed” links, are often used to transmit data from one integrated circuit to another within a computer system. In a typical differential link, one of the two devices attached to the link functions as a master device and the other functions as a slave. It is a common practice for the master device to initiate and perform a retraining process at regular time intervals to maintain link parameters and characteristics, such as the shape of the data eye, in an appropriate condition for reliable communication via the link.
There may be a trade-off involved in the timing of the retraining process. If the time interval between retraining processes is relatively short, the bandwidth provided by the link may be adversely affected. If the time interval between retraining processes is relatively long, the operating condition of the link may deteriorate such that the link fails to function.